AVONDALE, Ariz. — Jimmie Johnson didn’t have much warning, just a small vibration. And then his chances at a sixth Sprint Cup championship crashed along with his car at Phoenix International Raceway Sunday.

A melted bead in his right front tire caused the accident on lap 235, forcing Johnson’s car to the garage for 38 laps while the team made repairs.

Johnson’s 32nd-place finish, coupled with a sixth-place run for Brad Keselowski, turned Johnson’s seven-point lead into a 20-point deficit with only one race remaining in the Chase for the Sprint Cup. Keselowski can win the championship next week at Homestead-Miami Speedway.

“I hate to see it potentially end this way, but that’s racing,” Johnson said. “I’ve been doing this a long time. I’ve won a few championships and I’ve lost a lot.

“Losing isn’t any fun, but we’ll be back next weekend and next year hungrier than ever and do the best we can.”

Keselowski’s team didn’t tell him that it was Johnson who wrecked, but Keselowski saw Johnson’s car on pit road and knew he had just caught a huge break in the championship hunt.

The 28-year-old Keselowski will clinch the title if he finishes 15th or better at Homestead, 16th if he leads at least one lap or 17th if he leads the most laps. If Johnson doesn’t win the race, he has to finish 18 or 19 spots ahead of Keselowski, depending on whether they each earn bonus points for leading the race.

“You always want to be in the lead of the points, especially in the closing races, so I’m thankful for that,” Keselowski said. “But I also know that the troubles that they had are the same troubles that we could have next week, and so you try not to take anything for granted.

“You try to just focus on what lies ahead, and we’ve got to do the best job we can at Homestead.”

Keselowski nearly got caught up in the melee that erupted with seven laps remaining when Jeff Gordon retaliated against Clint Bowyer, causing a three-car wreck. Then his car got hit during a last-lap crash coming to the checkered flag.

“I just put myself in a position where no matter how it went down, I was going to be OK, and that’s thankfully how it played out to where I was OK,” said Keselowski, who raced conservatively after Johnson crashed. “I’d been briefed, I guess two laps prior that was going to happen (between Gordon and Bowyer), and so I was prepared.”

Johnson was just hoping for a top-10 finish, possibly a top-five, as he didn’t have a dominant car. He was expecting to lose spots to Keselowski, who ran ahead of him most of the race.

“I was content coming out of here within a few points up or down to him,” Johnson said. “I thought that was the way the day was going to turn out and go to Homestead and race like crazy and see what happens.

“But that tire going down changed that a lot. … I knew right when it hit the wall, we were going to be behind the wall working on the racecar in the garage area. The reality of that started sinking in quick.”

The reality is that Johnson no longer controls his own destiny after taking the Chase lead with back-to-back victories at Martinsville Speedway and Texas Motor Speedway. Johnson took the points lead from Keselowski at Martinsville, and then expanded it to seven points with the win last week at Texas.

“Today was proof that anything can happen in this sport,” Johnson said. “It takes a lot of pressure off. I would much rather have the pressure of trying to win a championship and try to hang on to the points lead.

“But in the position we have now, it really is a go-for-broke mentality.”